Bridging phenyl ligands. Unsaturated mercury-triosmium carbonyl cluster complexes containing bridging phenyl ligands

摘要

The gold phosphine group in the complex Os-3(CO)(10)(mu-eta(1)-Ph)(mu-AuPPh3), 1 can be replaced by mercury halide groups by reactions with mercury halides. The reaction of 1 with HgI2 yielded the new compound [Os-3(CO)(10)(mu-eta(1)-Ph)(mu-HgI)](4), 2 in 19% yield. The reaction of 1 with HgCl2 yielded the new compound Os-4(CO)(13)(mu-eta(1)-Ph)(mu-Cl)(3), 3 in 18% yield. When heated to reflux in cyclohexane solvent, compound 2 was converted into the compound [Os-3(CO)(9)(mu(3)-C6H4)(mu-H)(mu(3)-Hg)](2)Os(CO)(4), 4 in 11% yield. All new compounds were characterized by single-crystal X-ray diffraction analyses. Compound 2 is a tetramer of the unit "Os-3(CO)(10)(mu-eta(1)-Ph)(mu-HgI)" that is held together by a cubane-like Hg4I4 core having D-2 symmetry. Each triosmium cluster is formally electronically unsaturated and contains one edge-bridging phenyl ligand. Compound 3 contains a Os-3(CO)(10)(mu-eta(1)-Ph)(mu-Hg) cluster, but in this case the Hg atom bridges to an additional Os(CO)(3) group via three bridging chloride ligands. Compound 4 contains two Os-3(CO)(9)(mu(3)-C6H4)(mu-H)(mu(3)-Hg) clusters that are linked by a bridging Os(CO)(4) group. Each Os-3 cluster in 4 contains a triply bridging C6H4 benzyne ligand and one bridging hydrido ligand. (C) 2014 Elsevier B.V. All rights reserved.